Crimping tool



Jan. i4, 1958 Rv. WALKER 2,819,643

` 'CRIMPING TooL Filed March 9. 1955 A:a sheets-sheet 1l Jan. 4, 1958 R. v. WALKER 2,819,643

CRIMPING TOOL Filed March 9,* 1955 2 sheets-sheet 2 |IIHIHIIIIIIII My invention relates generally to crimping tools, and more particularly to a hand operated tool for crimping blasting caps or detonators around time fuses.

Detonators of the nonelectric type, used as primers for initiating `the explosion of dynamite and other explosives, usually comprise a copper or other soft metal tube closed at one end and containing a charge of a highly sensitive explosive, `such as fulminate of mercury, or a recently adopted equivalent substitute. A time fuse is adapted to be inserted in the open end of the tube or case,

and the latter then crimped so as to clamp the end of the fuse rmly in place. This crimping operation, using customary crimping tools, is dangerous because the detonating explosive within the cap is highly sensitive to shock, heat, and pressure. The possibility of an accidental explosion is suiciently great that men engaged inv demolition in the armed services are instructed to hold the crimping tool in the hand which is least favored, that is, in the left hand by right-handed men, and vice versa.

It is the primary object of my invention to provide an improved crimping tool in the use of which injury to the user is avoided in the event that the detonator should explode accidentally while it is being crimped around a time fuse.

. A further object is to provide an improved detonator crimping -tool as recited in the previous object in which the jaws are offset with respect to the handles, so that the detonator may easily be placed in the proper position for the crimping operation.

Other objects will appear from the following description, reference being had to the accompanying drawings, in which Fig. l is a perspective view of the improved crimping tool,` a portion thereof being broken away to show the relative position of a detonator about to be crimped;

Fig. 2 is a fragmentary perspective view, showing how the tool is used;

Fig. 3 is a side elevation of :the upper jaw and its handle;

Fig. 4 is a bottom plan view of the upper jaw and its handle;

Fig. 5 is an elevation of the upper jaw and its handle as viewed from the right in Fig. 3; and

Fig. 6 is an elevational view of the lower jaw and its handle as viewed from the handle end of the tool.

As best shown in Fig. l, the crimping tool of the invention is of plier-like construction, comprising a pair of handles 10 and 11 formed integrally with shanks 12 and 13 and jaws 14 and 15 respectively, the shanks being pivotally secured by rivet or bolt fulcrum means 16. The two handles 10, 11 together with the shanks 12, 13 and jaws 14, 15 formed integrally with the respective handles constitute a pair of levers adapted to scissor together about the fulcrum bolt 16. The shank portions 12 and 13 are provided with indented beveled edges 18 Cil 2,819,643 Patented Jan. 14,1958

and 19 which are cooperable to cut the timing fuse 22 to the required length.

As best shown in Figs. 3, 4, and 5, the upper jaw 15 projects sidewardly, or is offset, with respect to its shank 13. The downwardly projecting portion of the jaw 15 is tapered at 24 and has a generally semicircular notch 26 formed therein, this notch being bounded by a beveled surface 28 so as to provide a relatively sharp crimping edge or saddle for engagement with the casing of the detonator.

The lower jaw 14 extends sidewardly relative to its shank 12, and the guide and support portion 31 thereof has a circular hole 30 for the reception of a detonator cap 32. As indicated in Fig. 1, the explosive charge 33 of the detonator is positioned Well within an open end conical guard or shield 34 welded, brazed, or otherwise suitably secured to the support portion 31, which constitutes a detonation wall completely encircling the detonator hole 30. The jaw 14 includes means forming a crimping edge or anvil 36 spaced from the support portion 31, providing a groove 38 to receive the end of the upper jaw 15. As best shown in Fig. 6, the crimping edge 36 is generally semicircular, being formed by a beveled surface 40.

In using the tool, a suitable length of time fuse is cut from the supply by inserting it between notches 1S and 19 and operating the tool as a pair of scissors. The cut off length of the fuse is inserted in the detonator cap or casing 32 so as to bring the end of the fuse into contact with, or very close to, the explosive charge 33. rlhe detonator 32, with the time fuse thus loosely attached, is projected through the opening 30 in the guide portion 31 of the jaw 14 until the portion of the detonator to be crimped is in alignment with the cooperating portions of the jaws 14 and 15. Such insertion of the detonator is facilitated because the jaws 14 and 15 extend sidewardly from their shanks 12 and 13 and relative to the handles 10 and 11.

Upon closing the jaws, the casing of the detonator is positively crimped by the edges 26 and 36 of the jaws 15 and 14 respectively, tightly clinching the casing to the time fuse. As the jaw 15 crirnps the detonator casing its crimping engagement with the detonator is limited by the bottoming of the jaw 15 in the groove 3S so that excessive crimping of the detonator casing is prevented. It will be noted that the crimping edge 36 (Fig. 6) is not exactly concentric with the axis of the opening 30 in the guide portion 31 of the jaw 14 so that crimping, that is, indentation of the detonator casing, ytakes place on both sides of the casing, assuring a good mechanical connection between the time fuse and the casing.

While crimping the detonator, the tool should be held in the manner indicated in Fig. 2, with the open end of the shield 34 pointing downward and away from the body of the user. Thus, if the detonator accidentally explodes, the blast and the fragments of the detonator will be directed away from the user with no possibility of injuring him.

The moisture excluding plug of the high explosive charge to be detonated may be conveniently removed by using the pointed end of handle 11 as a pick.

While I have shown and described a preferred embodiment of my invention, it will be apparent that numerous variations and modifications thereof may be made without departing from the underlying principles of the invention. I therefore desire, by the following claims, to include within the scope of the invention all such variations and modifications by which substantially the results of my invention may be obtained through the use of substantially the same or equivalent means.

I claim:

1. A plier-like tool for crimping the casing of a detonator around a time fuse comprising, a pair of pivotally connected handles, jaws extending sidewardly from the handles beyond the pivotal axis of the handles, the first of said jaws comprising an apertured guide' and detonation deflect-ion member' vfor the reception of the detonator casing and having also a crimping elementspaced from the guide member to provide a groove, the Second of said jaws being positioned to be swung into the' groove and having a crimping edge cooper'able with the crimp'- ing element of the first jaw to engage the casing of a detonator inserted through the opening irl the guide member so as to deform the casing mechanically to engage a time fuse element inserted in the casing as the jaws are brought toward one another, and a hollow detonation shield secured to said guide and detonation deection member in encircling relation to said opening therein and extending outwardly with respect to the pivotal airis' of the handles in a direction opposite to that of the handles.

2. A detonator crimping tool comprising, in combina tion, two levers shaped to cross each other in mutual scissoring relation, fulcrum means pivotally connecting together intermediate portions of the two levers, said respective levers having two ends extending to one side of said fulcrum means and shaped to form a pair of operating handles, the end of one of said levers opposite the handle end thereof having means thereon forming a detonation wall, said detonation wall defining therein a detonator aperture completely encircled by the detonation wall, a hollow elongated detonation deflection shield of conical shape having a small end integrally secured to said detonation wall in encircling relation to said detonator aperture therein and having a large open end projecting away from the handle end of said one lever, means on said one lever dening a crimping anvil adjacent said detonation wall structure, and means on the end of the other lever opposite the handle end thereof defining a crimping saddle, said crimping anvil and said crimping saddle being concave toward each other, said crimping saddle being positioned on the other lever to move transversely relative to said detonator aperture into generally opposed detonator crimping relation to said crimping anvil as an incident to scissoring movement of said handles toward each other.

3. A detonator crimping tool comprising, in combination, two levers shaped to cross each other in mutual scissoring relation, fulcr'um means pivotally connecting intermediate portions of the two levers, said respective levers having two ends extending to one side of said fulcrum means and shaped to form a pair of operating handles, the end of one of said levers opposite said handle end thereof including means thereon forming a detonation wall, said detonation Wall dening therein a detona- -tor aperturel completely encircled by the detonation-wall', a hollow elongated detonation deflection shield of conical shape having a small end integrally secured to said detonation wall in encircling relation to said detonator aperture therein and having a large open end projecting away from the handle end of said one lever, said detonation wall end of said one lever having thereon an anvil element narrowly spaced from said detonation wall at the side thereof opposite from said detonation deflection shield and defining a concave crimping surface, said crimping surface having a minimum spacing from the extended axis of said detonator aperture somewhat shorter than the radius of said detonator aperture, the end of the other lever opposite the handle end thereof including a crimping saddle shaped and positioned thereon to move into the space between said detonator wall and said anvil element on said one lever as an incident to scissoring movement of said handles toward each other, said crimping saddle defining a curved crimping'suriface concave toward said anvil element crimping surface,4 and coacting abutments formed on said levers to limit move ment of said saddle toward said detonator aperture by scissoring of said levers.

4. A detonator crimping tool comprising, in combina`v tion, two levers shaped to crossv each` other in mutually scissoring relation, fulcrum means pivotally connecting .together intermediate portionsY of the two levers', tvfo ends of the respective levers extending to one side of said fulcrum means and being shaped to define a pair of oper# ating handles, means on the end of one of said leversl opposite the handle end thereof forming a detonator crimp'- ing edge and defining adjacent said crimping edge a deto-y nator aperture encircled by structure constituting a detof nation Wall, a hollow elongated detonation deilector in# tegrally secured at one end to said detonation w'all struc:-v ture in encircling relation to said detonator aperture .and having an open end projecting away from the handle end of said one lever, and means on the'end of 'the other lever opposite the handle end thereof, defining, a detonator crimping edge positioned on the other lever to be swung transversely to said detonator aperture into generally c p` posed detonator crimping relation to said crimping edge on said one lever as an incident to scissoring'rnovernent of said handles toward each other.

References Cited in the fue of this patent I UNITED STATES PATENTS Douglas May 28 1935 

